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Topic: The 2019 melting season (Read 1046912 times)

The longevity of the 'Crack' along most of the North American shore ["NAC: North American Crack" if it becomes a 'thing'.] (currently along most of Greenland and most of the Canadian Arctic Archipelago) is disturbing.

In spite of what the weather models sometimes report, the actual temperatures in the northern CAA have been very warm over the past several days. As discussed in previous posts, on July 14, 2019 the weather station at Alert, Nunavut hit 21C the warmest temperature ever measured north of 80 degrees Lat.

A team of field researchers just wrapped up a 2 week trip on Axel Heiberg and reported widespread permafrost melting. One of the researchers, professor Gordon Oz Osinski, said “in the 20 yrs since I started fieldwork in the Arctic I’ve never had such a long stretch of sun & temperatures in the teens [C].” To find the thread, open Twitter and search #AxelHeiberg2019.

Below is the link to the gif showing the permafrost melting. It is definitely worth a click. Pretty incredible sight when you consider that is happening at 79.8 degrees north latitude!

Despite the relatively benign weather of the past week, and spreading of the past by low domination, JAXA continues its rapid decline, down 380K km2 the past 3 days, and 920K over the past 10. Its now 150000 km2 ahead of 2012 on the date,

I can't see those numbers dropping off with the return of heat along the Russian coast, large moisture injections from the Pacific and the upcoming blowtorch from the Mackenzie valley onto the Beaufort sea and parts north of it. Especially given so much ice that's ready to melt.

I can't see a non- top 2 finish now, that would mean losing less than 3000000 km2 through Sept. A couple more 120K days now will pretty much guarantee it.

The 00z GFS is cataclysmic. The 12z EURO was not much different. It appears as though the CAA and CAB are about to take a major hit from D4-D10. We are already at record lows or close. I think the pre-conditioning in May and June combined with this upcoming pattern portends a likely chance of a new record low in terms of area / extent, and I think it is looking like we may now smash 2012's volume minimum. I could easily see a refreeze substantially worse than 2016-17.

7/21/2011 fell to 6.88, a drop of 70k.7/21/2019 needs a drop of 100k+ km sq for a record low for this date.

Analysis: Looking at Windy, compaction should be the norm for the 21st everywhere but western Siberia, but there is room for expansion and the strongest winds are there. Looks like a somewhat balanced day of expansion and compacting with more area contracting, so a little more than average. Call it a 100k drop for JAXA and tie the current low, +/- 10k.

Extended forecast:On July 2th, 2012 overtakes 2011 and remains the low until well after the Sept minimum. 2012 takes a big dive from 8/2 to 8/10 (I had previously misstated the drop as ending on the 9th) which it would be unlikely for 2019 to match given it was at least partially affected by the GAC (Great Arctic Cyclone.) As has been discussed elsewhere, one paper posited the warmth dredged up from that storm affected the minimum in 2012. Looking at the end of summer wide, droopy bottom, I'd agree. But the key really is that massive loss from 8/2 to 8/10. Whether that would have been lost more slowly or not is an academic issue: Absolutely unprovable as history has happened and will not be rewritten.

My point? The next four+ days may see extensive losses due to possible cyclones and dipoles. As you can see below, only 72k/day is needed to be in record territory before the 25th and the following three days' -125k average for 2012. I think 2019 may be in record territory tomorrow or the next day, and 100k+ losses over the next week may set 2019 up to keep pace with 2012's big week, making a new minimum that much more likely.

If 2019 is well back of 2012 on 8/10, I don't see a new minimum.

7/25/2012 fell to 6.62M km sq., record low for this date.2019 needs an average daily drop of 72k km sq. for a record low for this date.

Analysis: Looking at Windy, compaction should be the norm for the 21st everywhere but western Siberia, but there is room for expansion and the strongest winds are there. Looks like a somewhat balanced day of expansion and compacting with more area contracting, so a little more than average. Call it a 100k drop for JAXA and tie the current low, +/- 10k.

I'm not sure Windy is a good tool for looking at the winds - Nullschool has the vast advantaget of showing the globe rather than that irritatingly stretched semi-Mercator projection that Windy uses.

And looking at Nullschool, I notice a strong northerly wind in the Laptev, presumably leading to dispersion, and a cyclone over the Beaufort, and cyclones tend to disperse rather than compact the ice, so presumably leading to dispersion there. Other areas have little to no wind or (over Barents) wind that blows along the ice front.

So my take from Nullschool would be that the 21st has dispersion in those places where there is any wind to speak off.

As per Aluminium's gif above, dispersion rather than compaction seems to have been the norm recently, even so we have seen drops of over 330.000 km2 in the last three days. What the drop will be today I've no idea, any guess would just be a the result of random firing of neurons since I'm totally lacking in the prerequisits for prognostications: Empirical data combined with a tested predictive model.

Logged

because a thing is eloquently expressed it should not be taken to be as necessarily trueSt. Augustine, Confessions V, 6

I think the crack that has opened (for a few weeks now) north of the CAA will likely be persistent, and could be significant this year.

That video is scary, as his author says...Yes even if melting ice anchors temps to near 0, just a bit inland and uphill it can be much worse.

In all places it is energy (heat) and not temperature what matters, and 850 hpa level (1500 m or 5000 ft high) high temperatures over the ice mean hot air entering the pack, or descending (strong high pressure) or both, so it may not indicate ice surface temp but atmospheric energy flux.These last days the atmospheric energy flux has been negative, the direct sun energy reaching has been low, yet all the energy already stored in the pack and around the pack kept things going. Storm churning also increases melt rate since it “pulverizes” ice... Probably melting by now is losing its momentum at places, but the weather seems to change again.

In spite of what the weather models sometimes report, the actual temperatures in the northern CAA have been very warm over the past several days. As discussed in previous posts, on July 14, 2019 the weather station at Alert, Nunavut hit 21C the warmest temperature ever measured north of 80 degrees Lat.

A team of field researchers just wrapped up a 2 week trip on Axel Heiberg and reported widespread permafrost melting. One of the researchers, professor Gordon Oz Osinski, said “in the 20 yrs since I started fieldwork in the Arctic I’ve never had such a long stretch of sun & temperatures in the teens [C].” To find the thread, open Twitter and search #AxelHeiberg2019.

Below is the link to the gif showing the permafrost melting. It is definitely worth a click. Pretty incredible sight when you consider that is happening at 79.8 degrees north latitude!

I think the crack that has opened (for a few weeks now) north of the CAA will likely be persistent, and could be significant this year.

What you're seeing in the video is likely part of what's called a thaw slump. While the number of them has increased quite dramatically in the Arctic over the last few decades, they are also just a normal occurrence in many paraglacial landscapes and have occurred in the Arctic for millennia.They happen when layers of thick buried ice get exposed to the air. This can be by erosion from waves, rivers, or from things like heavy rain, which can cause the surface permafrost to detach. When the ice melts back, the soil on top slides down, mixes with the melt water and forms large flowing mud lobes at their front.Here's 2 examples from my own fieldwork in 2017

Hi everyone long time reader 1st time poster. I’ve been watching the arctic since 2012, more in the summer less in the winter. More in the high melt years less in the low. I want to thank Neven for this site and all the other contributors, too many to name but especially gentrocrat. I thought the other things with a description of the current weather was valuable to someone reading back in 10 years from now. Also Friv keeps it fun. Anyone else miss Dosbat? That dude was smart. Damn you brexit...

Anyways I never posted because I had nothing to add to the discussion. Keep up the good work everyone. I appreciate everyone who posts here even if I didn’t mention you.

Does everyone have to answer these questions every time? Or just cause I’m new? I know all the answers anyways...

It looks like the difference between 2012 and 2019 grows on smos.Pending the piomas update, it seems that the 2019 melting momentum is continuing everywhere, whilst 2012 starts to have a growing area where top melt has ended (beige pixel), meaning that there would be no safe zones in 2019 with very high thickness loss, even in the pole. 2012 has passed from a stronger melt where it was melting (maybe due to differences in ice that allowed for a wetter upper layer to be sustained), to only visibly stronger melt in the atlantic side, which means that 2019 is likely to remain lacking on that side but that it is overall better suited than 2012 to finish first in that data set, given that the atlantic side is mostly determined by side melt, and 2019 is better keeping the melt momentum everywhere else.The data also shows continued melt on the greenland north coast, while bremen has shown that concentration is low there, so, unless the weather pattern that allows fram export is restored, the crack will continue to grow, which is unusual so early in the season and could be the symptom of a changed paradigm.

Yep. Well it's only a model, though that would mean significant upwelling and probable mixing.edit: Looking at worldview suomi viirs brightness temperature band15, day it suggests water temperature is colder than the ice. I suppose that can happen.Maybe light fog over the ice https://go.nasa.gov/2JKpxLXGFS has air temp at 1.5C yesterday. click to run

What is the name of the island in the picture ? SE Kap Bridgman. I can find Kaffeklubben , northernmost terrafirma , but not the island in question.

I don't mean to be dramatic but if this comes to pass we are going to come 1-2M KM^2 away from a BOE and we may see a volume minimum 20-40% below 2012. The consequences this autumn and winter for the mid-latitudes (and elsewhere) will be very dire. Oh well.

I don't mean to be dramatic but if this comes to pass we are going to come 1-2M KM^2 away from a BOE and we may see a volume minimum 20-40% below 2012. The consequences this autumn and winter for the mid-latitudes (and elsewhere) will be very dire. Oh well.

Dire consequences yes. But at the same time if we do not have some sort of extremely shocking event, nothing is likely to change our current course towards making things worse and worse. The population needs a wake up event of startling magnitude.

I don't mean to be dramatic but if this comes to pass we are going to come 1-2M KM^2 away from a BOE and we may see a volume minimum 20-40% below 2012. The consequences this autumn and winter for the mid-latitudes (and elsewhere) will be very dire. Oh well.

Dire consequences yes. But at the same time if we do not have some sort of extremely shocking event, nothing is likely to change our current course towards making things worse and worse. The population needs a wake up event of startling magnitude.

The course will only continue. There is no fix. Any fix removes aerosols and then we have a BOE and the world ends. The best path forward is the current path. There is nothing you, me, or anyone else can do about it. If you think people will wake up when we have a near-BOE you are sadly mistaken. We still have weatherdouche88 posting about how nothing is happening this year, and it is actually tolerated and sanctioned on this forum given the fact he has not been banned -- if that's the case here, you think there will be change elsewhere? LOL. Ya right.

Since we're always presented with insolation during high pressure as the main reason for that to be bad for the ice and since the sun-angle where there is still more or less solid ice is already quite flat/low, this was by no means a stupid question.

Some exaggerations here and doomsday-buzzword feeds and sensationalism here are way more stupid IMO.

Last but not least call someone who ASKS a question instead of babbling away stupid isbad etiquette and the most stupid at the end of the day are those who don't ask.

Since we're always presented with insolation during high pressure as the main reason for that to be bad for the ice and since the sun-angle where there is still more or less solid ice is already quite flat/low, this was by no means a stupid question.

Some exaggerations here and doomsday buzzword feeds here are way more stupid IMO.

OK, fine, Siberia isn't on fire, the Arctic ice isn't already at a record low, and the forecast wouldn't beat 2012 by a mile. You are totally right. And we definitely are NOT only 40 days from solar maximum at the times of the impending extreme forecast.

It was meant as a genuine question. As far as I understand it, there is controversy about whether storms or sun are worse for the ice in the late season. There seems to be good reason to suspect that the 2012 GAC had a lot to do with that year's enhanced late-season melt. Well, I guess if we do end up with widespread high pressure instead of big storms this year, we can test that hypothesis (as Neven hopes), since so far this year's setup is arguably close to as bad if not worse than 2012.

It is going to get quite warm AND sunny over the CAB and Beaufort. This is pretty bad I guess. Attached ecmwf 12h run, T+6 (but looks like this from T+4 to T+10 basically), 850 hPa temp anomaly (yellow warm, blue cold)

There's a strong persistent dipole developing in the ECMWF that will last through the 10 day forecast period if it verifies. The heat and subsidence will continue over northern Canada and Greenland until further notice.

This is the weather that will put 2019 ahead of 2012 if this forecast verifies and I think it will because it is consistent with climatology and persistence of this summer's weather patterns.

FYI, the 850 temps we have seen in the past week do not indicate negative heat balance as far as I know. In some areas they indicate rising motions over the ice water. Clouds over these areas would have limited radiative heat loss and loss of energy from the ocean/ ice system. Warm air advection has been strong in the Kara sea over the past few days. Over all that has kept temperatures above freezing in most of the Arctic and has led to continued flow of heat from the atmosphere to the ice on average in the Arctic.